Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions fr...

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 636 to 641.

The idea of humans living on Mars has long been a subject of fascination for scientists and the public alike. Mars, often referred to as the "Red Planet," shares some similarities with Earth, such as the presence of seasons and a day-length comparable to our own. However, the planet's surface is covered with a layer of iron oxide, giving it its red appearance and making it vastly different from the blue and green hues of Earth. While its similarities intrigue researchers, significant challenges must be overcome before humans can call Mars home.

One of the primary obstacles is Mars's thin atmosphere, which is composed mostly of carbon dioxide. This means that the air on Mars is unbreathable for humans, and the lack of a magnetic field exposes the planet to harmful solar radiation. Scientists are exploring the possibility of creating habitats with controlled environments to protect humans from these harsh conditions. Terraforming Mars’s environment to make it more Earth-like has also been suggested but remains in the realm of theoretical science due to its enormous technical and resource demands.

Another challenge is the limited availability of water. Although evidence of frozen water and underground ice has been found, extracting and purifying it for human use requires advanced technology. Furthermore, the extreme temperatures on Mars, which can drop below -60 degrees Celsius, pose additional difficulties for survival and infrastructure. Additionally, dust storms on Mars can last for months and cover the entire planet, severely impacting visibility, solar power, and human activity.

Despite these challenges, space agencies like NASA and private companies such as SpaceX are actively working towards sending humans to Mars. Proposals include sending robotic missions to build habitats in advance and developing technologies for sustainable life-support systems. Engineers are also experimenting with 3D-printed materials to construct structures using Martian soil. If successful, humans may one day establish a permanent presence on Mars, paving the way for interplanetary colonization. While the journey to Mars is fraught with difficulties, the potential to expand human civilization beyond Earth remains an exciting prospect for the future.

(Adapted from Bright)

Trả lời cho các câu 636, 637, 638, 639, 640, 641 dưới đây:

Câu  636 :
Which of the following is NOT mentioned as a challenge of living on Mars?

A. Difficulties in providing access to breathable air for humans.

B. The need to protect habitats from long-lasting dust storms.

C. The risk of habitats being destroyed by strong winds.

D. Harmful radiation due to the absence of a magnetic field.